Question

Write and simplify a rational expression for the ratio of the perimeter to the area of rectangle if the width is 4x and the length is x+6

Answer 1

(5x + 6) : (2x² + 12x)

Explanation:

Perimeter = 2(length + width)

= 2[4x + x + 6]

= 2(5x + 6)

Area = length × width

4x × (x + 6)

4x(x + 6)

Perimeter : Area

2(5x + 6) : 4x(x + 6)

(5x + 6) : (2x² + 12x)

Answer 2

5x + 6 : 2x² + 12x

Explanation:

Width = 4x

Length = x + 6

Perimeter

= 2(4x + x + 6)

= 2(5x + 6)

Area

= 4x(x + 6)

Ratio of perimeter to area:

= 2(5x + 6) : 4x(x + 6)

= (5x + 6) : 2x(x + 6)

= 5x + 6 : 2x² + 12x